The actress brought her 12-year-old daughter along with her for the event, which celebrated her new film starring both Maya Hawke and Camila Mendes.
At the Hollywood Roosevelt event, Gellar, 44, rocked a shiny bronze dress and heels as he daughter, whom she shares with Freddie Prinze Jr., 45, was dressed in a hot pink blazer and a pair of white sneakers.
Do Revenge, from director Jennifer Kaytin Robinson, follows Hawke and Mendes as they tackle the problem of bullies in their high school. Gellar takes on the role of a headmaster at the school.
— camila mendes (@camilamendes) September 14, 2022
The Cruel Intentions actress told Entertainment Tonight on Wednesday that playing the role was "delicious."
"I think I felt the nostalgia, but I think I also felt the excitement of sort of the reincarnation of these kinds of movies because you never grow out of these," she said.
The film, which arrives on the streaming service on Friday, was notably inspired by Alfred Hitchcock's Strangers on a Train and also features a familiar face in Sophie Turner. The movie's trailer dropped back in August, showing the aftermath of a lewd video circulating the high school.
"After a clandestine run-in at tennis camp, [characters] Drea and Eleanor form an unlikely and secret friendship to get revenge on each other's tormentors," a synopsis for the film reads.
PATRICK T. FALLON/AFP via Getty
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Outside of their eldest daughter, Gellar and Prinze also share a 9-year-old son Rocky James.
Fans were able to see the family of four together when SMG posted a "vacation photo dump" earlier this year.
Gellar and Prinze celebrated their milestone 20th anniversary at the top of the month, while calling out Howard Stern, who insisted before the wedding that it "would not last."
"What do you think?" Gellar wrote to the SiriusXM host on Instagram. "I think you owe us."
In a 2021 interview with PEOPLE, the couple opened up about the early years of their relationship and how things have progressed for them. While Gellar said they started as "just two people at dinner catching up" before things took a turn, Prinze revealed that he realized soon enough SMG was going to be his wife.
"I didn't go on dates with other girls, nor did I even want to pursue dates with other girls," he said. "One day, I just knew we're going to get married and that I was going to propose. I didn't know when or how."